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April 1, 2015

April 1, 2015

Posted by **Larry English** on Friday, September 9, 2011 at 9:10pm.

a) Approximately 68% of the grades were between which grade?

b) Approximately what percentage of grades were between 55 and 76?

- Statistics -
**PsyDAG**, Saturday, September 10, 2011 at 1:34pma. 68% are mean ± 1 SD.

b. Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to the Z scores (from Z = -2 to +1).

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